Such an investment would mirror the efforts of the mystery trader known only as "50 Cent," who earned the nickname by buying gobs of volatility contracts roughly costing that much, set to profit from a spike in the fear gauge.

Also known as the VIX, the index in question is a measure of expected price swings in US equities that serves as a barometer for investor nervousness. It generally climbs as stocks fall, so purchases of VIX contracts translate to bearish wagers on the S&P 500.

At about 50 cents a pop, the aforementioned VIX call options expiring in 13 days have only been this cheap on a couple of occasions since the start of 2011, and not in three years, according to data compiled by Macro Risk Advisors. While the firm doesn't normally recommend buying volatility just because of low prices, they think it's more than reasonable right now.

"We have seen the VIX jump nearly instantly from extremely low levels to 20-plus," Pravit Chintawongvanich, the head of derivatives strategy at MRA, said in a client note on Monday. "Even a minor disruption to the recent placidity" could make the trade profitable, he wrote.

But buyer beware. It's been a tough road for the anonymous volatility vigilante more commonly known as 50 Cent. The trader has already seen $89 million in wagers expire worthless in 2017 as the VIX has remained at subdued levels, MRA data show.

The fear gauge was locked in a range between 10 and 14 for the first three months of 2017, and while it's since climbed as high as 15.96, it's been stuck well below 14 since a single-day plunge of 26% one week ago.

If you do decide to bet on a near-term VIX spike, 50 Cent would love to join you, except he or she already owns about 450,000 VIX calls expiring in May. As of late last week, the trader is now funneling money into bets set to expire in July and August. After all, volatility prices are collapsing, making longer-dated wagers more appealing.